1. Field
The present application relates to systems, methods, and media for controlling Session Initiation Protocol (“SIP”) overload.
2. Background Art
SIP is an application layer signaling protocol for creating, modifying, and terminating media sessions in the Internet. SIP has been adopted by major standardization bodies including 3GPP, ITU-T, and ETSI as the core signaling protocol of Next Generation Networks (NGN) for services such as VoIP, conferencing, Video on Demand (VoD), presence, and Instant Messaging (IM). The increasingly wide deployment of SIP has raised the requirements for SIP server overload management solutions. A SIP server can be overloaded for many reasons such as emergency induced call volume, flash crowds generated by TV programs (e.g., American Idol), special events such as “free tickets to third caller”, or denial of service attacks.
There exists a need to addresses a SIP-over-TCP overload control problem. There is also a need to utilize the existing TCP infrastructure to solve the overload problem without changing the SIP protocol specification as is needed for the UDP-based application level feedback mechanisms.